Rep. Darrell Issa (R-CA) and IRS Commissioner John Koskinen (R) talk before a House Oversight and Government Reform Committee hearing on "Examining the IRS Response to the Targeting Scandal" on Capitol Hill in Washington March 26, 2014. (REUTERS/Yuri Gripas)

Just 72 hours after Rep. Paul Ryan scolded Koskinen and barked “I don’t believe you. … Nobody believes you,” Issa is gearing up for his own showdown with Koskinen, who refused to provide Issa’s staff this weekend with information about the loss of Lois Lerner’s emails and IRS email storage policies.

Issa’s Oversight Committee requested that the IRS make available IRS deputy chief counsel for procurement and administration Thomas Kane for a transcribed interview about the destruction of Lerner’s emails, but the IRS refused. Oversight Committee staff next requested a briefing from the IRS on its email retention programs, but the IRS did not provide it.

Koskinen testified before the House Ways and Means Committee Friday that some of Lerner’s emails from the period 2009 to 2011 were destroyed after her computer allegedly crashed and that six other IRS employees related to the conservative targeting scandal also experienced computer crashes. The Daily Caller reported that the IRS canceled its relationship with its email-archiving contractor Sonasoft just weeks after Lerner’s crash.

The current IRS commissioner’s claims to technical incompetence are undermined by the fact that he led President Clinton’s much-celebrated President’s Council on Y2K Conversion, successfully updating all of the federal government’s computer systems for the new millennium. And Issa is making known that he does not plan to let Koskinen off the hook. (VIDEO: Paul Ryan Goes Ballistic On IRS Commissioner Over Lost Emails)

Issa prepared 15 specific questions for Koskinen, giving him no later than 5 p.m. Monday, two hours before the hearing, to answer all of them in full. Those questions, provided to TheDC, are summarized below (The following is not the exact text from Issa, but rather our own summary of the questions):

1. Explain, in detail, Lois Lerner’s 2011 hard drive failure, including the date it happened, and give the names of all employees who worked on retrieving data from it.

2. When did you learn that the hard drive failure affected the Oversight Committee’s subpoena into the IRS targeting scandal, and which IRS staffers realized that the subpoena could not be fulfilled?

3. Explain all the steps the IRS took to retrieve data from Lerner’s hard drive.

4. Name all IRS employees that worked on agency email servers between 2009 and 2014.

5. Name all IRS contractors that worked on agency email or hard drive systems.

6. Give the names of the IRS employees most knowledgeable about email servers and data retention.